States of Matter

• What are the three states of matter?

  Solids, liquids, and gases
• What determines the state of a substance?

  Temperature and pressure
• At what points do state changes occur?

  At the melting point and boiling point
• What occurs at the melting point?

  Melting and freezing
• What occurs at the boiling point?

  Boiling and condensing
• How do individual atoms differ from bulk matter?

  They do not share the same properties
• How can the three states of matter be represented?

  By a simple model with small solid spheres
• What affects the energy needed to change states?

  The strength of the forces between particles
• How does the strength of forces between particles relate to melting and boiling points?

  Stronger forces lead to higher melting and boiling points
• What type of change is changing states of matter?

  A physical change
• What happens to particles during melting?

  They absorb heat and gain kinetic energy
• What is the melting point (m.p.)?

  A specific temperature for melting
• What is the difference between boiling and evaporation?

  Boiling forms bubbles inside the liquid
• What is the boiling point (b.p.)?

  A specific temperature for boiling
• What is freezing?

  When a liquid changes into a solid
• What is the relationship between melting point and freezing point?

  They are the same temperature
• At what temperature does water freeze and melt?

  0 ºC
• What is required for freezing to occur?

  A significant decrease in temperature
• What is evaporation?

  When a liquid changes into a gas
• At what temperatures can evaporation occur?

  Over a range of temperatures
• Where does evaporation occur in a liquid?

  Only at the surface of the liquid
• What factors increase the rate of evaporation?

  Larger surface area and warmer liquid surface
• What is condensation?

  When a gas changes into a liquid on cooling
• What happens to gas particles during condensation?

  They lose energy and group together
• What is sublimation?

  When a solid changes directly into a gas
• What is the reverse of sublimation called?

  Desublimation or deposition
• What are state symbols in chemistry?

  • Indicate the physical state of substances
  • Written after each formula in equations
  • Shown as subscript, e.g., NaOH(aq)
• What does the state symbol (s) represent?

  Solid
• What does the state symbol (l) represent?

  Liquid
• What does the state symbol (g) represent?

  Gas
• What does the state symbol (aq) represent?

  Aqueous or dissolved in water
• What does the term 'aqueous' relate to?

  It means the substance is dissolved in water